1. Field of the Invention
The present invention relates generally to an image encoding apparatus, method and program for encoding images entered by a device with an image input function, for example, a mobile telephone with a camera, and more particularly to an image encoding apparatus, method and program for encoding images using values of the density, chroma, etc., of the images.
2. Description of the Related Arts
Recently, with the increasing use of the Internet by mobile telephones, mobile telephones mounted with image input devices, such as cameras or scanners have been enthusiastically developed. By use of such mobile telephones, image data acquired by the image input devices can be sent for utilization from the mobile telephones to terminals such as another mobile telephone or personal computer through a communication network including the Internet.
A method for utilizing image data, in which image input devices such as scanners or cameras are connected to personal computers is disclosed, for example, in Specification and Drawings of U.S. Pat. No. 5,636,292. In this image data utilization method, image data, such as printed matters, where the information acquired by Steganographic encoding (hereinafter referred to as “stegano data”) is embedded, is read from the image input devices into personal computers for detecting stegano data.
However, in most cases, the way of embedding information like stegano data in images is a digital watermarking technology for security, like forgery prevention or abuse prevention, and even if the original data is deformed or partially used, the embedded information must stand such abuses without being broken. For this purpose, very complex methods had to be employed, such as the methods, in which the same data is dispersedly embedded within the image, or in which the data is inserted within a frequency area.
Recently, however, this digital watermarking technology is being used for a variety of value added services. For example, Specification and Drawings of U.S. Pat. No. 5,636,292 disclose a method, wherein stegano data, digital watermarking data, embedded in printed matters is read by the personal computer, the read stegano data being sent to a server for acquiring a URL, such that a specific web page is displayed.
However, the processing of entering images and reading digital watermarking data takes a relatively large amount of calculation. For this reason, even if the mobile telephone with a camera tries to read digital watermarking data to provide a service corresponding to the image, the mobile telephone cannot execute such a service in practical processing time due to the restricted processing performance of memory or a CPU that can be used in the mobile telephones.